bracketed blenny vs blennioid

bracketed blenny and blennioid both are nouns.

Word	Noun	Adjective	Verb	Adverb
bracketed blenny	Yes	No	No	No
blennioid	Yes	No	No	No

As nouns, blennioid is a hypernym of bracketed blenny; that is, blennioid is a word with a broader meaning than bracketed blenny:

bracketed blenny: small eellike fishes common in shallow waters of the northern Atlantic
blennioid: elongated mostly scaleless marine fishes with large pectoral fins and reduced pelvic fins

Other hypernyms of bracketed blenny include blennioid fish.

bracketed blenny (noun)	blennioid (noun)
small eellike fishes common in shallow waters of the northern Atlantic	elongated mostly scaleless marine fishes with large pectoral fins and reduced pelvic fins